LONDON - Scientists have discovered a genetic link to baldness that helps explain why some men may inherit their shiny pates from their fathers.
Tests on more than 1,000 bald men revealed two gene regions that, active together, make a man seven times more likely to lose his hair. About 14 per cent of men are thought to carry both gene variants.
The findings give scientists a much clearer picture of the genetic causes of male pattern baldness, which affects roughly a third of men by the age of 45. Genetic factors are thought to account for at least 80 per cent of the condition.
In the long term, the latest work is expected to pave the way for genetic treatments for hair loss, but more quickly it could be used to identify men who are likely to lose their hair prematurely. These men may benefit by beginning baldness treatments before they start showing signs of hair loss, the researchers said.
The search for baldness treatments has already seen the rise of a multimillion-pound industry in Britain alone, where an estimated eight million men are affected.
One of the genes identified by the scientists was already known. It sits on the female X chromosome, meaning it is only passed from mother to son. The second gene region the study identified is new and gives researchers their first clue to how baldness may be passed from father to son.
The tests showed one gene or more on chromosome 20 contributes substantially to male pattern baldness, although it is not clear what the genes do.
Two teams, one led by Tim Spector at King's College London, the other by Axel Hillmer at Bonn University, report similar findings in the Nature Genetics journal. "The one in seven men who carry both these risk factors are almost certain to go bald before the age of 50," Mr Spector said.
The quest for baldness treatments irks some, who object to the assumption that shiny domes are undesirable, but Mr Spector said many men experienced psychological problems, including a loss of self-confidence, when their hair began to thin.
Male pattern baldness, where hair is lost from the temples and the crown, is the most common form of hair loss and is caused by an increase in a chemical called dihydrotestosterone, or DHT.
This chemical makes hair follicles produce thinner and thinner hairs until the follicles die off. - ( Guardian service)